Landscape and nursery
§ Homeowner guide to emerald ash borer treatments
§ Emerald ash borer insecticide treatment information for tree care professionals
§ Maximizing the effectiveness of backpack herbicide applications
Turfgrass
§ Winterkill on golf courses
§ Early spring turf tips
§ Lawncare 101 DVD
Christmas trees and forestry
§ Getting a jump on spring with Christmas tree scouting
§ 2005 Christmas Tree Insect Forecast Table
§ Christmas Tree IPM Scouting Guide
Other news
§ Transporting agricultural supplies classified as hazardous
§ Weather news
Welcome to the first issue of our 2005 publishing season. We asked the Landscape Alert authors to ignore the two inches of snow that fell on the MSU campus last night and instead think about spring. Their articles in this issue will help you start preparations for the warmer conditions that are surely headed our way.
We are interested in your ideas and suggestions – please, feel free to contact us at catalert@msu.edu or 517-353-4951.
Several insecticide products are available to homeowners for control of emerald ash borer (EAB). Treatments are needed every year in order to protect ash trees from EAB. Treatments are recommended only for homeowners in the quarantined area; it is not necessary to treat ash trees outside of this area. At this time the quarantined area includes all of Monroe, Wayne, Macomb, St.Clair, Lenawee, Wasthenaw, Oakland, Lapeer, Hillsdale, Jackson, Livingston, Genesee, Ingham, Shiawasee, Saginaw, Branch, Calhoun, Eaton, Clinton and Gratiot counties. Research tests have shown that we can protect healthy trees from emerald ash borer with insecticides, but we may not be able to save severely compromised trees. By the time you see dead branches, thinning of the canopy, and woodpecker activity, the tree is already severely damaged, and it may be too late to save it with insecticides.
Insecticide products available for home use include Bayer Advanced Garden™ Tree and Shrub Insect Control, Bonide® Systemic Insecticide Bullets and ACECAP ® 97 Systemic Insecticide Tree Implants. Caution: read all label instructions before using any pesticide, avoid skin contact and store pesticides where children cannot reach them.
Bayer Advanced Garden™ Tree and Shrub Insect Control is a systemic insecticide applied as a soil drench around the base of trees. There are several Bayer Advanced Garden™ products, be sure to purchase the one with “Tree and Shrub” in large print on the label and imidacloprid as the active ingredient. Label instructions say to use 1 ounce of the insecticide for every inch of distance around the tree trunk (circumference). For example, a 20-year-old ash tree may have a trunk diameter of 10 inches and a circumference of 25 inches. For this tree you will need 25 ounces of insecticide. Pour 25 ounces of Tree and Shrub Insect Control into a bucket, fill it ¾-full with water, then pour the solution around the base of your ash tree. Applications should be made in mid to late April. This product is available for about $25 at most local hardware and garden stores; it is sold in 32oz., blue, plastic containers.
Bonide® Systemic Insecticide Bullets and ACECAP® 97 Systemic Insecticide Tree Implants are similar products, both containing acephate as the active ingredient. The insecticide is delivered through small cartridges implanted in the trunk. Implants should be placed at 4-inch intervals around the trunk base. To determine the number of implants required, measure the trunk circumference (distance around the tree trunk) in inches at 4 ft. above the ground, then divide the circumference by 4. Using a tape measure, drill 3/8-inch diameter holes at 4-inch intervals starting approximately 6 inches above the soil surface and spiraling up and around the trunk base. Holes should be drilled 1 ¼ inches into the tree from the cambium (layer below the bark) surface. Press implants into drilled holes as far as possible, then use a hammer and a flat end punch or dowel rod to drive implants into the tree, slightly beneath the cambium surface. Both products should be applied in early May, during the period of maximum upward flow of tree sap. ACECAP® 97 is available through authorized dealers (see list below); Bonide® Bullets can be purchased at Ace Hardware or from one of the retailers listed below.
It is currently recommended that homeowners treat small trees with a trunk diameter of 6 inches or less (approx. 19 inches circumference) using only the Bayer Tree and Shrub Insect Control product. For trees larger than 6 inches in diameter (approx. 19 inches circumference), Bayer Tree and Shrub Insect Control should be used in combination with the ACECAP® 97 or Bonide® Bullets for the first year or two of treatment, after which only the Bayer Tree and Shrub Insect Control is necessary. Treatments may be more effective if overall tree stress symptoms are reduced, therefore it is recommended that trees are fertilized in the fall or spring, watered regularly, and lightly mulched around the base to retain moisture.
Environmental
Horticulture
Begick Nursery &
Garden Center, Bay City
Bordines (all
locations)
Carefree Lawn
Center, Trenton
Cohoon’s Garden
Center, Midland
Downtown Home &
Garden, Ann Arbor
English Gardens (5
Locations)
Evergreen Home and
Garden Center
Plymouth Nursery
& Garden Center
Soulliere Garden
Center, St. Clair Shores
Utica Farm Bureau,
Utica
Meijer- all stores English
Gardens, all locations
Harry's
Garden Center, Warren
7 Mile Garden Center, Redford Flowerbarn
Nursery, Sterling Heights
Melvins Ale
Hardware, Walled Lake D&L
Garden Center, Taylor
Allemon's Landscape
Supply, Detroit Cow Bell Lawn
& Garden, Brighton
Youngs Garden Mart,
Warren Big Acre
Store, Brighton
Panetta"s
Landscape Supply, Westland Auburn
Oaks Garden Center, Rochester Hills
Leppek Nursery,
Brighton Chelsea
Farmers Supply, Chelsea
Telly's Greenhouse,
Troy Marcials
Home & Garden, Oakland
Wojo's Greenhouse,
Ortonville Freemans
Pet & Garden, Holly
North Monroe Greenhouse,
Monroe The Hobbit Place II,
Jackson
Carefree Lawn
Center, Trenton Gee
Farms, Stockbridge
Shady Stop of
Brighton Utica
Farm Bureau, Utica
Abele Greenhouse,
Saginaw Barretts,
Adrian
Christians
Greenhouse, Williamston Gleis
Orchards & Greenhouse, Hillsdale
Feed 'N Seed, Port
Huron Eagle
Landscape Supply, Southfield
ACECAP® 97 dealers
in Southern Michigan
Environmental Horticulture
Begick Nursery & Garden Center
5993 W.S. Saginaw
Road
Bay City, MI 48706
Bordines (4 Locations)
Rochester Hills
Clarkston
Grand Blanc
Brighton
Carefree Lawn Center
2805 Van Horn Road
Trenton, MI 48183
Cohoon’s Garden Center
802 Townsend Street
Midland, MI 48640
Downtown Home & Garden
210 S. Ashley Street
Ann Arbor, MI 48104
English Gardens (5 Locations)
Clinton Township
Dearborn Heights
Eastpointe
Royal Oak/Troy
West Bloomfield
Evergreen Home and Garden Center
36000 Groesbeck Hwy.
Clinton Township, MI
48035
Plymouth Nursery & Garden Center
9900 Plymouth-Ann
Arbor Road
Plymouth, MI 48170
Soulliere Garden Center
23919 Little Mack
St. Clair Shores, MI
48080
Utica Farm Bureau
6981 Auburn
Utica, MI 48317
Soon after emerald ash borer was first identified, many people wanted to know if they could protect individual trees with insecticide applications. The message from MSU Extension was that we expect insecticides applied for the emerald ash borer (EAB) to work about the same as they do for a very closely related insect, the bronze birch borer. However, since this borer was a new pest -- we also said that we can't be certain insecticides will work as well until we conduct some research tests. Unfortunately this was interpreted by some to mean that nothing works for EAB. Now, we have completed two seasons of extensive insecticide tests, and some insecticide treatments are providing excellent control of EAB. The first year of test results are available at the emeraldashborer.info web site. Here is a summary of the 2003 tests, with the products listed by percent control when treated trees are compared with trees that were not treated. Results are not listed below for the Pointer trunk injection because a 12% ai formulation was provided for the 2003 test instead of the standard 5% ai formulation.
Imicide trunk injections in late May (imidacloprid)
Injectacide-B trunk injections in late May (bidrin)
2 applications (May 30, July 2) of Tempo
1 application of Onyx (May 30)
2 applications of Onyx (May 30, July 2)
2 applications of Sevin (May 30, July 2)
Merit soil injections (imidacloprid)
2 applications of Orthene (May 30, July 2)
1 application of Sevin
1 application of Tempo (May 30)
1 application of Orthene (May 30)
In 2004, ash street trees in Troy, Michigan were used to test some of the same products and some new ones. Complete results are available at the emeraldashborer.info web site. The table below gives a quick summary of the results:
|
Treatment |
New galleries/m2 |
Larvae/m2 |
|
Arborjet 5% IMA-jet |
0.0 - 1.2 * |
0.0 - 0.5* |
|
Acecap |
3.5 * |
2.8 * |
|
Onyx sprays (several treatments) |
3.8 - 11.8* |
1.9 - 8.9 * |
|
BotaniGard |
6.9 |
4.7 |
|
Mauget Imicide |
8.3 |
6.2 |
|
Merit soil drench |
12.8 |
10.0 |
|
Untreated dontrol |
14.7 |
10.1 |
|
* Indicates
significant difference from the Untreated Control by Tukey’s LSD at p<0.05 |
||
For more information on the research described above and on several other projects, go to emeraldashborer.info and click on "research" on the left side of the screen. This will take you to 17 different research reports that you can print if you like. More reports will be appearing later this spring from EAB studies conducted in 2004.
While many brands of backpack sprayers are available and all brands basically come in one of two types: diaphragm and piston. Piston sprayers are typically cheaper than diaphragm and will often provide greater pressures (up to 90 psi). While diaphragm pumps may cost more and provide up to 60 psi of pressure, this type is usually more durable. If spray mixes such as wettable powders are used (or other formulations containing clay), then diaphragm should be selected, as these materials will wear out a piston pump rather quickly.
Calibration is one of the most important aspects of any pesticide application. Proper calibration insures that the applicator knows exactly what rate of pesticide is being applied. An Ohio State Extension publication on calibrating hand-held sprayers can be found here: http://ohioline.osu.edu/for-fact/0020.html
The Michigan State University Pesticide Education Program also has information on backpack sprayer calibration, some of which is available here: http://www.pested.msu.edu/BullSlideNews/bulletins/pdf/Category2/Chap4.pdf
Selection of the proper herbicide and appropriate rate will always be the major determinant of weed control. Of course, product selection depends on correct identification of the weed species to be controlled. Once the weed species are identified, refer to herbicide labels and Extension publications for product selection. Most herbicide labels can be accessed online at the distributors website or at: www.cdms.net or www.greenbook.net
Herbicide recommendations are available for nursery crops in Management Practices for Michigan Wholesale Nurseries (www.hrt.msu.edu/BMP/order.htm) and the MSU Extension pest management guides for herbaceous or woody plants (Bulletins E2782 and E2783). Herbicide recommendations for Christmas trees can be found in the Christmas Tree Pest Manual (E2676, new revision available later this year).
Good maintenance practices are essential for long-term effective use of backpack sprayers. Before spraying, run clean water through the sprayer and check for any leaks. Numerous leaks or cracks in sprayer parts may indicate that the life of the sprayer is over. After use, proper cleaning is the most important maintenance practice. Not only will this prevent clogging and solid build-up on internal sprayer parts, but it will also reduce or eliminate any chance of contamination with the next use. To clean a sprayer, flush the tank, lines and all parts with clean water. Next, fill the sprayer with water and mix in ammonia or a strong soap. Spray the cleaning solution through the nozzle(s) and then flush the sprayer again with clean water. Drain the sprayer and remove nozzles, screens and strainers. Finally, scrub all accessible parts with a stiff bristle brush, reassemble and flush again with clean water. Never put a sprayer away for storage without proper cleaning.
As an alternative to the “hand-pump” sprayers, some backpack sprayers are commercially available that use carbon dioxide to provide pressure. These can be built with pressure regulators so that the exact output of spray is known at all times. Various tank sizes are available ranging from two-liter bottles to five-gallon canisters. Boom length and the number of nozzles on a boom can also be specifically designed to fit a wide range of needs. Special nozzle tips may be used on the boom ends so that applicators may make one pass through a polyhouse and cover the entire area. The main supplier for these sprayers and parts is R&D Sprayers with the website: http://www.co2sprayers.com/
A catalog may be ordered by calling (337) 942-1001.
Depending on the sprayer brand, many attachments may be available. Shields, hoods or cones may be purchased or designed to fit over the wand and allow directed or shielded applications. These attachments can prevent the spray solution from contacting desirable foliage and allow applications closer to crop plants than with an uncovered nozzle. Pressure regulators may also be purchased for certain sprayers to maintain a constant maximum spray pressure.
To regulate pressure from hand-pump sprayers, a Constant Flow Valve (CFValve, also called nozzle mount pressure regulator) can be added to the wand. This valve opens when a pre-set pressure is reached and closes when the pressure drops. These features allow the CFValve to act as both a pressure regulator and a check valve (no dripping). Regulating pressure will allow the applicator to determine the exact spray output so that proper rates will be used. These valves are available and are designed to fit many of the commercially available hand-held sprayers. Two commercial sources for this product include Forestry Suppliers (www.forestry-suppliers.com, (800) 647-5368) and M. K. Rittenhouse & Sons (www.rittenhouse.ca, (800) 461-1041). A formal article on this valve may be viewed at: http://gilb.cip.cgiar.org/downloads/Others/Workshop2001/4_Application%20Technology.pdf
Making predictions is always challenging but as the snow continues to subside and temperatures warm, golf course superintendents across Michigan are definitely concerned about the potential of winterkill on golf courses.
Winterkill is a very general term commonly used to define turf loss during the winter. Winterkill can be caused by a combination of factors including desiccation, low temperature stress from cold winter winds, or crown hydration injury associated with rainfall/snowmelt followed by a rapid drop in temperature. Due to the unpredictability of environmental factors, and differences in other factors such as surface drainage, the occurrence of winterkill on golf courses is variable and can vary greatly between golf courses and even across the same golf course.
When winterkill is a problem, it is often annual bluegrass (Poa annua) greens and fairways that are the most susceptible. Annual bluegrass is especially susceptible to winterkill from crown hydration injury. The problem occurs in late winter, when daytime temperatures became warm enough that the annual bluegrass plant begins to take up water (hydrate). It is possible that this occurred during the most recent thaw from March 5-7 when, for example, temperatures in the Lansing area reached a high of 48°F and then as a cold front moved through, dropped to a low of 13°F on March 8. During this period there was a significant melting of snow and then refreezing of the water that had yet to drain away. The reason crown hydration is a problem is because during these events, ice crystal formation can occur in the crown of the plant. Ice crystal formation will rupture the plant cells and ultimately cause the plant to die.
Annual bluegrass is more susceptible to crown hydration injury because it emerges from dormancy and begins taking up water earlier than creeping bentgrass. Creeping bentgrass remains in the dormant state longer, and therefore does not take up water and become susceptible to crown hydration injury during late winter.
At this point it is difficult to assess the extent of damage or for that matter even if there was widespread damage. To assess if damage has occurred, samples can be taken from turf areas, moved inside and placed in a sunny area to see if the turf greens-up. If there is no green-up within a couple weeks, the turf was killed.
If turf was lost, to facilitate recovery of damaged areas, greens should be lightly fertilized with nitrogen to stimulate growth. In past years, inter-seeding creeping bentgrass into dead areas on the greens has given mixed results. On greens predominantly annual bluegrass, often it is better to scratch the surface of the dead areas to allow the annual bluegrass to germinate and fill in the voids.
Spring? Even though the calendar is telling us it’s almost spring, I’ve yet to really feel it. It appears that temperatures are going to begin to warm in the next couple of weeks but I think it’s still going to be a little bit before the turf really gets going.
Before we get started on any discussion of turf practices for home lawns let’s talk mowers. Your assignment this weekend if you choose to accept it, is to find where your mower is and secondly to un-screw that blade and take it down to the local hardware store to get sharpened. If you take action now, you’ll miss the big lines because most lawn warriors will be glued to the tube for some NCAA basketball. Sharp blades are important not only from an aesthetics perspective but a clean cut reduces water loss and helps prevent pathogen infection in the turf.
Winter has definitely been a long one this year in Michigan and if I had to guess, I think we will definitely see some snow mold in some turf areas. There might be some pink snow mold and in other areas some gray snow mold. Whichever is your favorite color, I wouldn’t get too worked up over the symptoms you’ll see. Gray snow mold is typically seen in turf areas that were under snow cover for extended periods of time. The damage from either type of snow mold is typically restricted to the leaf tissue and once the temperature starts to warm, the turf will start growing and recover from the damage quickly.
Keeping in mind that it’s March 18 and our next issue isn’t until April 15 (don’t forget your taxes!), I’ll give you some tips that can be done in the next month. It’s hard to imagine that anyone would be mowing this weekend but by mid-April, let’s hope so!
Lowering the mowing height for the first mowing will help remove dead tissue and facilitate soil warming which will help the turf get growing faster. Be advised though not to get carried away with this lowering the mowing height recommendation. At most I would drop it 1 inch from your normal mowing height – be careful, we don’t want to scalp the turf. For most, dropping the height a half-inch (usually 1 notch on your mower) will probably suffice to clean up debris on the lawn from the winter and get that turf going. Lowering the height a notch will be especially helpful for turf with snow mold damage. You also might want to consider raking the turf in areas that the turf was really matted down to help stand it up and then mow it off.
Resist the urge to apply something, anything, to your turf right now to help wake it from its winter slumber. We’d like to see that turf growing before we apply either a preemergence herbicide (i.e. crabgrass preventer) or fertilizer. If you applied a late fall fertilizer application you may not need to apply an early spring fertilizer, but instead might be able to wait until mid-May. Avoid the urge to get out there and fertilize the turf out of dormancy. This is the time to show restraint and let the turf naturally awaken. Applying high rates of fertilizer now will encourage excessive top-growth and has the potential to reduce summer stress tolerance later on. You might notice that professional applicators will start to make applications in the next month. They are most likely doing preemergence herbicide applications and/or light fertilizer applications. The fertilizer amounts they are applying are probably 0.5 lbs. N/1000 ft.2 or less, just enough to encourage some greening without causing excessive growth.
Remember that the environmental signal for applying a preemergence herbicide is when the forsythia bush is in full bloom. You can also use a soil thermometer to check soil temperatures. Apply preemergence herbicides when soil temperatures at a two-inch depth reach 50°F. In Michigan, the time for applications is usually around April 15 for mid-Michigan. Before you automatically apply a crabgrass preventer, consider whether or not crabgrass is a big problem in your turf. Remember that the best way to control weeds in turf is to encourage a healthy, dense turf that competes well with weeds and crowds them out. Mowing high, returning clippings and having a good fertility program are just some of the practices that will encourage a dense turf.
Ten informative lessons
from the experts at Michigan State University are now available in DVD format.
Dr. Kevin Frank and Ron Calhoun provide a quick guide to lawn renovation and
lawn care with these topics:
§
Turfgrass Selection
§
Lawn Renovation
§
Mowing
§
Watering
§
Grubs
§
Fertilizer
§
Thatch
§
Crabgrass Control
§
Mulching Leaves
§
Broadleaf Weed Control
The DVD is available through the MSUE Bulletin office for
$19.95. For more information or to purchase the DVD, contact the bulletin
office at 517-353-6740 or find them on the web at:
http://www.emdc.msue.msu.edu/
Search for publication E2937 or title Lawncare 101.
It has been cold, snowy and dreary, but it will soon be time to think about aphids, adelgids, borers, weevils and other pests! Take time now to walk through your fields and examine your trees carefully. What sorts of insect damage are left from last year? Do you see galls on your spruce trees? Did white pine weevil kill the terminal leaders of some of your pine or spruce trees? How do the needles of your Douglas fir trees look – are they curled or bent from Cooley adelgid? Maybe you see little white pine needle scales or maybe black sooty mold on your Scotch pine needles. Don’t forget to look at the stems of your trees. Big pitch globs on the stem usually mean that Zimmerman pine moth is present.
Good scouting is one of the most important parts of integrated pest management (IPM). It helps you get a jump on insect pests that may cause you problems this year, tell you if the problem is located in one spot or generally across the field, and whether the damage is enough to require treatment. In a few weeks, some of our early season pests will begin their activity. So now is the time you should be planning your scouting and management activities for some of our early season pests.
Zimmerman pine moth is an insect that can be a real problem if you have Scotch and Austrian pine. This insect overwinters as a tiny caterpillar and bores under the bark early in the spring. It will tunnel under the bark for several weeks during the summer causing large soft masses of pitch to flow from the tree. Zimmerman pine moth larvae usually bore into large branches or more commonly, into the stem of the tree, often right at the branch whorls. The tunneling can kill branches, and tree stems may break off above the wound.
If you plan to use an insecticide to control this pest, the insecticide must be on the bark as the caterpillar bores in (mid- to late April) otherwise, it will be well protected under the bark for the rest of its life cycle. In addition to applying the insecticide early, it is also important to adequately cover the bark of the stem and large branches. If you are unable to get good coverage, then spraying will not be effective!
Also, we have found that trees attacked the previous year were more likely to be attacked again. This means you need to look for heavily infested, individual trees. Cut and destroy those trees by chipping or burning them as early in the season as possible. That should help remove the most attractive trees from the field and will kill the developing larvae.
White pine weevil is another insect that becomes active early in April on warm spring days. Overwintering adults move from the litter to the treetops to mate and lay eggs. In the past few years, we have seen increasing damage (dead leaders on white pine, spruce and Scotch pine). Controlling this pest involves applying a registered pesticide to control the egg-laying adults. Make sure to thoroughly cover the leader and the upper part of the tree. Then in the growing season when you see leaders beginning to die, clip them out and remove them from the field. We will be setting out traps at several locations this year to monitor the emergence of the overwintering adults.
Be thinking about Pales weevil if you have trees that have sustained damage in the last one to three years. These weevils overwinter as adults in the litter and duff. They are attracted to fresh pine stumps to lay eggs. The larvae feed around the root collar and in the big roots of the stump. That's not a problem -- you don't sell stumps, right? The adult weevils actually cause the problem, as they will gnaw away on the bark of shoots, below the needles. This feeding causes the shoot to die and flag. They will feed on several different conifer species including white pine, Scotch pine, Fraser fir and Douglas fir.
If you have fresh pine stumps near or mixed in with live trees, and you have a problem with Pales weevil, you can spray the bark area of the fresh stumps with a registered, persistent insecticide. This will need to be done in spring, usually sometime between early and late April, depending on your location and the weather.
Cooley's adelgids will also complete their life cycle on Douglas fir. They do not form galls on the tree. Instead, the adelgids appear to be small, white cottony balls, usually on the undersides of the needles. Their feeding can cause small, yellow necrotic spots on the needles. When populations are heavy, the needles will be distorted and appear to be "clenched" around the shoots.
Again, scouting is important. There are several windows in which you can control this pest. Watch for tiny black nymphs early in the spring. These are the overwintering females. The nymphs will cover their bodies with cottony-appearing white threads where they will lay 10 to 30 eggs. These will hatch around the time that buds are breaking and move to the newly formed needles to continue feeding. When the females and nymphs are out from under the cottony mass, is the best time to apply an insecticide. Another spray may be needed in mid-summer, when another generation of nymphs begins feeding on Douglas fir.
Farmers routinely transport agricultural supplies that are classified as hazardous materials. Depending on quantities transported and trip destinations, they may need to have vehicle placards and a federal hazardous materials transportation security plan. Hazardous materials and threshold quantities that require placards and a transportation security plan are:
§ Gasoline, 119 gallons
§ Anhydrous, 119 gallons
§ Pesticides, 119 gallons or more than 1000 pounds
§ Diesel, 119 gallons
§ Others, to be detailed in bulletin E-2575
In general, transporting hazardous materials (except anhydrous ammonia and other compress gases) from the farmstead to the field, from field to field, or from field to the farmstead is exempt from the federal hazardous materials transportation requirements.
Transporting hazardous materials over the threshold quantities, from the supplier, or to town to pick up supplies or other farm-related functions is not exempt. Under these circumstances, farmers need to placard and have a transportation security plan. Farmers that transport anhydrous ammonia need to comply regardless of the trip destination. Michigan authorities enforce federal hazardous material transportation requirements.
The transportation security plan will be added to the
emergency planning bulletin E-2575 when it is revised in 2005. In the meantime
there is a PowerPoint slide set (w/speaker notes) and handout on this topic at
the MGSP internal website:
http://www.kbs.msu.edu/mgsp/Resources/Transporting%20Hazardous%20Agricultural%20Supplies.ppt
Following abnormally mild temperatures during much of February, the development of a persistent upper air troughing pattern over eastern North America led to the onset of true winter weather over the Great Lakes region during the last week of the month. Temperatures that were with much below normal and periodic snowfall has been reported over much of the region ever since. Current medium range forecast calls for the upper air trough to break down by next week and be replaced (at least temporarily) by more west to east zonal flow across North America and a moderation in temperatures. Collectively, the outlook suggests that most overwintering vegetation will remain dormant for at least the near future.
In the short range, an area of low pressure centered over the central Great Plains Friday morning (March 18) will slowly approach and pass through southern sections of the Great Lakes region during the next 48 hours. With access to Gulf of Mexico moisture, this system will bring the likelihood of precipitation to the state Friday night and continuing periodically through Saturday evening or Sunday morning. The precipitation is expected to fall in the form of snow in most areas of the state initially, but will likely mix or change over to rain in southern and central sections by Saturday (March 19). Several inches of accumulation are possible by Saturday evening from sections of the Upper Peninsula southward into northern and central Lower Michigan. Temperatures will remain well below climatological averages for the next few days with highs ranging from the upper 20s and low 30s far north to the mid and upper 30s far south through Sunday. Low temperatures will range from the teens north to low 30s far south. Drier weather is expected statewide by early next week with a slow moderation in temperatures. Daytime readings may reach the mid- or upper 40s by next Wednesday in southern sections.
Looking further ahead, most recent medium range forecast guidance is hinting at a change of the upper air pattern that has persisted for the past few weeks with more zonal flow expected by the last week in March. Regardless, very cold air is still present at the surface across large sections of northeastern North America, and some of this air is likely to affect northern sections of the United States including the Great Lakes region during the next one to two weeks.
The latest NOAA Climate Prediction Center 6-10 day outlook for March 23-27 calls for below normal temperatures for nearly all of Michigan. With the primary storm tracks remaining north and south of Michigan, drier than normal conditions are forecast. In the 8-14 day time frame, the eastern troughing pattern persists with a continuation of below normal temperatures statewide. Precipitation totals are forecast to increase to near normal levels.
The weak El Nino conditions that have persisted in the equatorial Pacific for the past several months are now showing signs of dissipation. The NOAA Climate Prediction Center long lead outlook for the next few weeks calls for equal odds or “climatology” scenario (i.e equal odds of below-, near-, and above normal values) for both temperature and precipitation for almost all of the state except for southeastern Lower Michigan, where cooler than normal temperatures are expected. The equal odds/climatology scenario is also indicated statewide for temperatures and precipitation for the three-month March-May 2005 period, although a forecast area of above normal precipitation extending from the southwestern United States through the southern and central Great Plains and into the central Corn Belt brushes extreme southwestern sections of the state.